They usually wait till the last second before getting the laptops to try and get the most recent model. The real value is the software loaded on with them. Many people liked the tablet feature but I found people tended to use it more at first and then went back to typing with occasionally circling something. I rarely used it, but then I stopped going to lecture too.
There has been some talk for a while to stop the laptop/PDA stuff and get an iPad, but I don't think that will come to fruition because of the battery and what not. Originally, the laptop was more because earlier classes weren't great with technology and it is easier to replace parts when all machines are the same. Now, they will probably stick with it because of the computer based testing and pushing updates, but I know schools that do computer testing without mandatory machines as well. They will bludgeon you to death with stuff that is probably second nature to you, but not to them. (This may be biased since I'm a tech person)
As far as open house, bring parents if you want. A lot of people do. If they are going to help fund your education, it may be nice for them to see what they are funding. If not, it would still be nice to show them if they want.
If you haven't gotten an interview yet, there is still hope but I would operate under the assumption you won't get an interview at this point. If you don't have any other acceptances, you need to get the ball rolling on what you're going to do to strengthen your app during the off time.